Hand arc lamp



Aug. 3o, 1927. 4 1,640,793

S. M. MEYER HAND ARC LAMP l /V cwi 47 Q @w Z4. Y um# O INVENTOR. 4J 0 A 57i/v0 M. M5227? Q 4 O Patented Aug.. 30, 1927.

TES

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SVEN!) M. MEYER, F BROOKLYN, NEW YORK, ASSIGNOR, BY MESNE ASSGNMENTS, OF THIRTEEN-FORTIETHSTO SVEND M. MEYER, OF WOOBHAVE'N, NEW YORK, AND TWENTY-SEVEN FORTIETHS T0 WLLlIAM JAMES, OF BROOKLYN, NEW YORK.

HAND 'ARO LAMP.

Application tiled February 20, 192. Serial No. 89,696.

The object of my improvement is a hand arc lamp, particularly for the purpose of reflecting light onto objects to be photographed and for all purposes wherecontinuous operation of the lamp is not required. 4For instance for photographic purposes it is seldom necessary to operate such a vlamp more than one-half or one minute, though the improvements made by the present invention permit much longer operation with the hand control lmechanism shown and described. The novel combination of elements of which this lamp is constituted permits an easy handling of the lamp without separate accessory parts such as resistance or choke coils or the like, all

that is necessary to put the lamp into operation being the connection of the lamp by a flexible cord to any commercial electric supply circuit whether this be alternating or direct current. rlhe' advantages accruing from this novel combination greatly increase the use of such lamps for portable purposes, inasmuch as owing to its comparatively 'small size it can easily be carried in a coat pocket.

My invention is illustrated in the accompanying drawings in which- Figure 1 represents a side elevation of a hand arc lamp according to my invention, port-ions thereof being shown in longitudinal vertical section on the line 1 1, Figure 2; v v

Figure 2 represents a top view of the lamp;

Figure 3 represents a front view seen from the direction in which the light is reected; l y

Figure 4: is a transverse section of the carbon release mechanism taken on the line 44-4, Figure 3; y

Figure 5 is a longitudinal vertical section of this V mechanism taken on the line 5 5, Figure 4; and

Figure 6 is a bottom view of the lamp,

the protecting casing being removed.

i Referring to, Figures 1, 2 and 3, 1 is a base. plate on which are mounted, insulated therefrom b bushings 2, two carbon holders 2 and 3 y means of screws 4. .In order to frictionally hold the -zcarbons` 14 inserted in these holders, the latter are 'castellated at their free ends as shown at 15"so that these ends may ,yieldingly press against the carbone. On another portion of base plate 1 is mounted a standard which consists of' two tubular elements 5 and 6 braced by a handle 7 also mounted on base plate 1 as shown. Standards 5 and 6 and handle 7 are sufficiently rugged to permit the carrying of the entire lamp by means of handle 7. rlubular standards 5 and 6 contain each a plunger 8 and 9 respectively which are coupled together by means of a bracket 10 which is forked as shown in Figure 2 and carries at each of its forked ends a holder 11, 12, respectively forl the upper carbons 13 which cooperate with the lower carbons 14 to produce the arc in the well known manner.

Upper carbons '13 each are freely slidable y in their respective holders so that they will drop vby their own weight onto the lower carbons 14. Plungers 8 and 9 which thus support thru the bracket 10 the two upper carbon holders together with their carbons are counter-balanced by springs 16 housed in the tubular standards, the tension of these springs being sufficient to push the plungers by means of detent 17 against the adjustable stop 18 mounted on one of the standards. This serves as a limit on the uppermost position which the' upper carbon holders may assume for a certain adjustment made at 18. Detent 17 which is fixed to plunger 9 protrudes thru a slot 19 provided in standard 6.

-The means for holding the upper carbons 13 in their respective holders 11 and 12 in a desired position are as follows.

These carbon holders, for instance 11 in Figures 1, 4 and 5 have a portion of the side wall cutV away such as is shown for instance in Figure 5, at 30, so that the carbon is exposed at that portion to the outside. A shackle 31 loosely pivoted to a bracket 32 fixed to the carbon holder extends across cutaway portion 30 of the holder so that it is enabled to frictionally contact with the carbon. A tension spring 33 fastened to the free end of shackle 31 is fastened at its other end to bracket 10 as will appear from Figures 1 and 2 so that shackle 31 is thereby held against carbon 13 preventing it from slipping down in its holder. A fixed guide 34 is fastened to the bracket 32 and extends past shackle 31, following substantially its contour a slight distance away from it how- Y following the cam surface 38 ever, and extending with its right-angularly bent end into an opening provided at the free end of shackle 31. This guide merely has the purpose of preventing the free end of shackle 31 from moving up and down,

though a certain slight play is permittedI pen that the one pair of carbons is brought in contact when thumb disk 36 is epressed for the purpose of striking the arc whereas the other pair which happensto have burned off more during the previous Juse of the lamp would still remain out of contact so that the arc cannot be struck in either pair, the two pairs of carbons being connected in series with each other as will be referred to in detail later on. To avoid this the following means are provided for each upper carbon holder. Adjacent to the free end of each shackle 31 a tripping finger 37 is located and fastened at its rear end to the standards 5 and 6. This free end is slightly rounded ott as shown at 38 and extends sufficiently close to the free end of shackle 31 that when the upper carbon holders are depressed as previouslyydescribed, the shackle end will strike rounded off portion 38 short of its eXtreme end so that when the upper carbon holders are further depressed shackle 31 in will be lifted ofi' its carbon 13, enabling the latter to freely drop down thru its holder until it strikes the lower carbon. If now thumb disk 36 is released both upper carbons are simultaneously removed from their lower carbons and both arcs will be struck at the same time, and whenever the upper carbon holders arrive at their extreme upper portion', the distances between the two pairs of carbons, i. e., the two arcs, will be of the same length. During the operation of the lamp the 0perator can follow up with the upper carbons by slightly pressing onto thumb disk 36 to maintain the arc approximately at the same length, or if he should-momentarily desire to have greater light intensity he may even temporarily shorten the two arcs.

The shackles 3l remain removed from their respective carbon-s so long as each shackle is enga ed by its cam surface 38 and they lock the carbons in their 4holders as soon as thumb disk 36 is raised for the purpose of striking the are. For slightly increasing the weight of the upper carbons and for the purpose of the connecting pig tail 53 to these carbons heavy rings 39 are attached to the upper ends of carbons 13.

rlhe cylindrical reflector 40 is removably Iattached to standards 5 and 6.by means of serve at the same time as choke or ballast coils in case the lamp 1s supplied-with alternating current. These coils may best be seen in Figure 6 with regard to their arrangement relatively to each other. I have provided three coils 45, 46 and 47. The two coils .45 and-46 are arranged near the outer edge of base plate 1 and are both wound alike with an odd number of layers each, in the present case three layers of which two layers are counter-wound relatively to each other so that the. respective lmagnetic fields produced by them will neutralize each other. The third layer is then the only layer which is inductively effect-ive. Itis of course obvious that more than three layers may be used so long as a certain number of layers is wound opposite to an equalv number of the other layers and so that only the remaining layers of the total number remain inductively effective. The purpose of this arrangement is that, for instance by using three layers I am enabled to use a very heavy resistance wire which would not unduly heat` at the current load used for the comparatively short time during which the lamp burns. Such a heavy resistance wire being of course quite long in order to produce the resistance required, would when coiled up thruout its entire length in a coil wound thruout in the same direction produce too great an inductive effect. In case of direct current these coils act purely as ohmic resistances, and owing to the low specific current load which-the wire has to carry these coils will not unduly heat. The center coil 47 is wound thruout with a similar heavy resistance wire in the same direction, however, :for all layers, but for cooling purposes the coil is comparatively long and the layers Iare arranged in banks such as is shown at 4 The circuit connection of these coils with the carbons and the supply line is as follows. Two plug pins 50 and 51 are fixed in a block of insulating material 52 at the rear end of the lamp and the current passes properly fastening recarga from plug pin 51, thru coil 46 lower carbon holder 2 thence thru the lower and upper` carbon 14, 13, thence thru pig tail 53 lto the other pairy of carbons down to lower holder.` 3 and thence over coil '47 and thru coil 45 to plug `pin 50. The two outer coils 45 and 46 are arranged with respect to the polarity of the field produced by them such that adjacent endsof the coils have the same polarity,l whereas the center coil 47 extends with its thin end to about the center of the two outside coils and is wound insuch a direction that` the polarity at this -inner end of the coil is'opposlte to the polarity of the ends of the outer coils pointing in that direction. For instance I have indicated the polarity of the ends of the out.- side coils adjacent. to the connecting plug with N, N and accordingly the end of coil 47 pointing :in the same direction should have a south polarity which I have illustrated with S. Byv thus arranging the coils I avoid any excessive chattering of the lamp. when supplied with alternatingr current.

For the purpose of -coilsa per-foratedcasing is attached' to the lower sidelof base plate 1 as may be seen in Figures 1 `and 3.' While I have shown and described a lamp prvided with two sets of carbons, I do'not wish to limit myself to this number, inas-f much as additional sets may beV provided, each `set havin a release mechanism such as shown and escribed and hand operated from a common point conjointly and coextensively with the mechanisms` of the other sets.

1. A hand arc lamp having two pairs of l vertically disposed carbons mountedvside 'by side and being electrically connectedin series with -'each other, a stationaryvholder for.

the lower carbon of each pair and a hand Vcontrolled vertically moveable bracket and holder for the'upper carbons mountedionsaid bracket, a guide forl said bracket and a spring supporting said bracket and tending thence thru i y to prevent it prutecting the ballast` to hold it in raisediposition, a spring pressed shackle for each upper carbon holder nerinally engaging the carbon contained therein from freely sliding, a tripping arm for each shackle disposed to lift it from its carbon when the' bracket is depressed beyond a predetermined amount to permit the upper carbon to freely slide into contact with lts lower carbon and an adjustable stop for holding means from said carbon when its holder is moved more than a predetermined amount towards the lower carbon to permit the upper carbon to freely slide lonto the lower carbon, and three steadying` imped-, ance airY c ore coils wound of suitable resistance wire and arranged beneath said base said coils having less than halfthe total number of vtheir layers counter-wound relatively to a similarnumber of the remaining layers to reduce the im edance .eiect of the` total number of layers or agi-ven length of resistance lwire lcontained in the coil,l the third of said coils being bank wound,-the two counter-wound coils being laced with plate and in circuit with said carbons, two of similar poles adjacent to each ot er and one `end of the bank wound coilextending longitudinally midway betweenthe other coils, said coil end havin 'ai .polarity opposite'to that of the endsofgthe'outer coils'pointing ifn itgalllie same direction for the purpose set` -SVEND 1M.v MEYER. 

